Why Does a Single Hit of Weed Make Me Faint?
One night in 2005, at a party at my house, two things happened: I had a single toke from a joint, and a friend introduced me to her new boyfriend. For most people this confluence of events would be no problem, but my body was not having it. As my friend’s boyfriend dribbled on about his adventures in Peru, his fluffy hair began to morph and swirl. The more it swirled, the more I wanted to vomit. Then his voice started piping down through a tiny hole in the roof, then… nothing. It was lights out. That was the first time it happened, but soon enough it became apparent that this was my fate. I could not inhale marijuana—not even a little bit, not even sans alcohol—without blacking out. But why? Is my constitution so delicate, just a whiff of weed requires its total shut-down?
One of the only studies conducted on this phenomenon was published in 1992. Researchers from Duke University gave ten healthy men a strong joint to smoke while standing up, and reported that six participants felt “moderate” to “severe” dizziness. Those who experienced severe dizziness also showed marked decreases in blood pressure, which went as low as 60 mmHg.
The standing-up part is key because it indicates weed could bring on something called orthostatic hypertension, low pressure caused by the movement or position of the body.
“Marijuana can cause quite profound lowering of blood pressure, and cause users to faint as not enough blood gets to the brain,” confirms Dr. Andrew Mongomery, a general practitioner. “A lesser lowering of blood pressure may lead to a sense of dizziness without actually passing out, [although] the biological mechanisms underlying this are highly complex and incompletely understood.
“Marijuana can also lead to anxiety,” he adds, “with a secondary effect of dizziness—or act on the brain directly to create a sense of rotational dizziness.”
Blood vessels dilate, causing the brain to be deprived of oxygen and thus blacking out.
Dr. Harry McConnell, a Professor of neuropsychiatry at Griffith University’s Menzies Health Institute, says the reason behind a weed-related fainting spell depends on the situation and the individual. Aside from a possible drop in blood pressure, “it could also be seizures that cause blackouts, or the other chemicals mixed with it. After all, Marijuana is not pure, so it might have recreational chemicals mixed with it. People may not be aware of those ingredients.
“Marijuana might [also] cause vasodilation,” Dr. McConnell continues, “where blood vessels dilate, causing the brain to be deprived of oxygen and thus blacking out. Sometimes episodes of vertigo can also cause blackouts.”
Then there is the possible effect of other recreational substances, possible other drug interactions, personal medications, or medical conditions. A study from 2002 noted that while weed’s “cardiovascular effects” are not associated with serious health problems for most young, healthy users, people with cardiovascular disease could be putting their health at risk. This is “because of the consequences of the resulting increased cardiac work, increased catecholamine levels, carboxyhemoglobin, and postural hypotension.”
Whatever the reason behind your body’s hatred of the herb, accept that the weed life may not be for you, and get yourself seen to. “[Fainting from marijuana use] is not certainly uncommon,” confirms McConnell. “It’s recognized. But it’s always important to go to a doctor and get evaluated.”
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One toke and I'm out.
These Warning Signs Could Mean You’ve Overdosed on Marijuana
Since many states have now legalized recreational marijuana use, many more people are now comfortable lighting up (or at least, they’re admitting it more often). And while smoking or ingesting pot is considered safer than alcohol consumption, that doesn’t mean it is without potentially harmful side effects.
While the common belief is that it’s impossible to overdose on marijuana, as it turns out, that may not be true. While no one has ever died from too much marijuana, it’s definitely possible to have too much. Here’s how to tell when it’s time to put down the pipe (or the brownies).
You feel dizzy
Woman feeling dizzy | iStock.com/ AntonioGuillem
According to Leaf Science, dizziness is a common symptom of heavy marijuana use. If you start to feel dizzy or disoriented, sit down, sip some water, and wait it out. The weed will leave your system eventually, but the dizziness can last quite awhile.
Next: Marijuana is sometimes used to ease anxiety, but sometimes it backfires.
You have anxiety and paranoia
Woman feeling anxious | iStock.com/Viktor_Gladkov
For some people, any amount of marijuana causes anxiety — but for others, it can actually help alleviate it. But one sure sign that you’ve smoked too much pot is suddenly feeling very anxious. Unfortunately, much like dizziness, all you can is wait it out.
Next: If your heart is racing, it’s time to stop smoking.
A pounding heart or chest pain
Woman with chest pain | SIphotography/iStock/Getty Images
Marijuana can increase your heart rate, and a racing heart is a definite sign you should slow down. TCH makes your blood vessels expand, which can lower your blood pressure and cause your heart to speed up to compensate. If you have a history of heart troubles, you may want to stay away from cannabis entirely.
Next: This side effect is rare, but it happens.
Uncontrollable shaking or seizures
Person having a seizure | Martinbowra/Getty Images
The good news is, you’ll have to ingest a lot of marijuana for this to happen. The bad news is that too much can, in fact, cause uncontrollable shaking and even seizures. If this happens, someone should call 911 immediately.
Next: This is a terrifying sign you’ve overindulged.
Woman hallucinating | KatarzynaBialasiewicz/Getty Images
Too much marijuana can make you hallucinate. This is terrifying, and it happens most often when the potency is stronger than the smoker expected. Legalization has helped this become less common since the strains are more regulated and labeled.
Next: Cannabis is used to treat nausea, but sometimes it can cause it.
Nausea and vomiting
Woman throwing up | LarsZahnerPhotography/Getty Images
While marijuana is often used medically to combat nausea, if you have too much of it, it can actually lead to nausea and vomiting. Fortunately, these effects are typically short-lived and will leave your system as the THC does.
Next: Here’s what to do if you’ve smoked too much.
What happens when you’ve overdosed?
Spilled pill bottle | GillTeeShots/Getty Images
Whether you’re a regular stoner or a first time smoker, ingesting too much is possible, even though marijuana has better labels now. Since smoking too much is not a life or death emergency (unless, as mentioned above, you’re having heart palpitations and sweating), treating marijuana intoxication is typically a waiting game. Get to a comfortable environment, preferably with someone who is capable of taking care of you. You’ll return to your sober state soon.
When it comes to marijuana consumption, too much of a good thing is certainly possible. Here's how to tell when to put down the pipe.